The Role of Thyroid Disorders, Obesity, Diabetes Mellitus and Estrogen Exposure as Potential Modifiers for Pulmonary Hypertension

A study on the genetic comorbidity between autoimmune diseases and pulmonary hypertension: an observational study and POST-GWAS analysis

Background: The causal relationship between various prevalent autoimmune diseases (ADs) and pulmonary hypertension (PH) has yet to be fully understood, and the contribution of genetic factors to their coexistence remains largely unexplored. Methods: We utilized Post-GWAS and the Medical Information Mart for Intensive Care (MIMIC) database to investigate the relationship between autoimmune diseases and PH. Results: After a series of MR Analyses, only Type 1 diabetes Mellitus (T1DM) (OR = 1.06, 95% CI 0.99-1.13, P = 0.083; OR = 1.07, 95% CI 1.02-1.13, P = 0.005) and primary biliary cholangitis (PBC) (OR = 1.10, 95% CI 1.05-1.15, P = 8.22E-5; OR = 1.08, 95% CI 1.03-1.14, P = 0.002) emerged as significantly correlated with PH. Additionally, reverse MR indicated that PH could trigger the development of systemic lupus erythematosus (SLE) (OR=1.090, 95% CI = 1.014-1.171, P = 0.014). An observational study using real-world data found a clear association between rheumatoid arthritis and increased risk of PH after adjusting confounding various variables (OR = 1.39, 95% CI 1.11-1.75, P = 0.005). Furthermore, the genetic correlation results between the diseases: T1DM & PAH: P (LDSC) = 1.20e-11, P (GNOVA) = 3.36e-08; PBC & PAH: P(LDSC) = 9.40e-07, P (GNOVA) = 5.17e-05. Conclusions: Our study indicates a genetic correlation and shared risk genes between PH and autoimmune diseases, offering insights into the mechanisms underlying their co-occurrence and potential implications for future therapeutic strategies.

Unveiling the metabolic challenges in pulmonary arterial hypertension: Insights into thyroid, glycemic, lipid, and bone disorders

This study aimed to evaluate the prevalence of thyroid, glycemic, lipid and metabolic bone disorders among adult patients with pulmonary arterial hypertension (PAH).

METHODS

This was an observational cross-sectional clinical study with patients with PAH, matched by sex and age with a control group without PAH. All individuals were enrolled into a clinical assessment, metabolic workup, thyroid ultrasound, and bone densitometry protocol.

RESULTS

The PAH group included 35 participants (34 females, 46 ± 15.5 years), and the control group, 40 (39 females, 41.8 ± 13.1 years). There was no difference in body mass index (BMI) between PAH and control group (27.5 ± 5.9 and 26.9 ± 4.3 kg/m2, respectively, p = 0.63; 95 % CI: -1.8, 2.94), neither in physical activity time per week (60.3 ± 103.3 and 98.9 ± 137.6, respectively, p = 0.17; 95 % CI: -95.23, 18.06). Although there was no difference in the prevalence of insulin resistance between the PAH (51.4 %) and the control group (47.5 %), p = 0.74, patients with PAH had a higher median of glycated hemoglobin (A1c) than the control group (6.1 % and 5.57 %, respectively, p = 0.006; 95 % CI: -0.14, 1.22). PAH group presented lower mean total cholesterol (170.46 ± 35.51 mg/dL) and median LDL-cholesterol [105 (83-129) mg/dL, median (P25-P75)] levels than the control group [192.1 ± 34.44 mg/dL, p = 0.009; 95 % CI = -37.76, 5.52 and 121.6 (97-145) mg/dL, p = 0.012; 95 % CI: -34.08, 0.77, respectively]. It was found a higher prevalence of hypothyroidism (22.9 %) in PAH group than in control group (2.5 %), p = 0.007. We found hyperparathyroidism (HPT) among 8 patients of PAH group (23 %), but none in the control group. Considering bone mineral density disorders, 12 patients from PAH group presented low bone mass, osteopenia, or osteoporosis (34 %), and 8 individuals in the control group (20 %), p = 0.032, which represented a 2.13 higher relative risk for those conditions for the former group. The patients with HPT presented a higher creatinine level (0.98 ± 0.12 mg/dL) than the PAH patients with normal parathyroid hormone (0.76 ± 0.14 mg/dL), p = 0.0004; 95 % CI: 0.12, 0.33. The PAH group also presented lower total hip (-0.15 ± 1.25) and femoral neck (-0.14 ± 1.07) bone mineral density (BMD) Z-scores than the control group (0.50 ± 1.13, p = 0.021; 95 % CI: -0.18, -0.027 and 0.35 ± 0.94, p = 0.038; 95 % CI: -0.16, -0.01, respectively).

CONCLUSION

In this cohort, the findings of higher A1c levels, hypothyroidism prevalence, lower LDL and total cholesterol levels, and a higher prevalence of hyperparathyroidism, as well as lower total hip and femoral neck BMD Z-scores in the PAH group, compared to the control group and highlighting the dysregulation of various metabolic pathways in patients with HAP, suggesting the need for targeted interventions to enhance patient care. Additionally, they underscore the importance of gaining a deeper understanding of the mechanisms driving these changes and their potential pathophysiological connections to the disease.

Sex Dimorphism in Pulmonary Arterial Hypertension Associated With Autoimmune Diseases

Pulmonary hypertension is a rare, incurable, and progressive disease. Although there is increasing evidence that immune disorders, particularly those associated with connective tissue diseases, are a strong predisposing factor in the development of pulmonary arterial hypertension (PAH), there is currently a lack of knowledge about the detailed molecular mechanisms responsible for this phenomenon. Exploring this topic is crucial because patients with an immune disorder combined with PAH have a worse prognosis and higher mortality compared with patients with other PAH subtypes. Moreover, data recorded worldwide show that the prevalence of PAH in women is 2× to even 4× higher than in men, and the ratio of PAH associated with autoimmune diseases is even higher (9:1). Sexual dimorphism in the pathogenesis of cardiovascular disease was explained for many years by the action of female sex hormones. However, there are increasing reports of interactions between sex hormones and sex chromosomes, and differences in the pathogenesis of cardiovascular disease may be controlled not only by sex hormones but also by sex chromosome pathways that are not dependent on the gonads. This review discusses the role of estrogen and genetic factors including the role of genes located on the X chromosome, as well as the potential protective role of the Y chromosome in sexual dimorphism, which is prominent in the occurrence of PAH associated with autoimmune diseases. Moreover, an overview of animal models that could potentially play a role in further investigating the aforementioned link was also reviewed.

Differential inhibition of sildenafil and macitentan on saxagliptin metabolism

The development of diabetes mellitus (DM) is generally accompanied by erectile dysfunction (ED) and pulmonary arterial hypertension (PAH), which increases the use of combination drug therapy and the risk of drug-drug interactions. Saxagliptin for the treatment of DM, sildenafil for the treatment of ED and PAH, and macitentan for the treatment of PAH are all substrates of CYP3A4, which indicates their potential involvement in drug-drug interactions. Therefore, we investigated potential pharmacokinetic interactions between saxagliptin and sildenafil/macitentan. We investigated this speculation both in vitro and in vivo, and explored the underlying mechanism using in vitro hepatic metabolic models and molecular docking assays. The results showed that sildenafil substantially inhibited the metabolism of saxagliptin by occupying the catalytic site of CYP3A4 in a competitive manner, leading to the alterations in the pharmacokinetic properties of saxagliptin in terms of increased maximum plasma concentration (Cmax), area under the plasma concentration-time curve from time 0 to 24 h (AUC(0-t)), area under the plasma concentration-time curve from time 0 extrapolated to infinite time (AUC(0-∞)), decreased clearance rate (CLz/F), and prolonged terminal half-life (t1/2). In contrast, a slight inhibition was observed in saxagliptin metabolism when concomitantly used with macitentan, as no pharmacokinetic parameters were altered, except for CLz/F. Thus, dosage adjustment of saxagliptin may be required in combination with sildenafil to achieve safe therapeutic plasma concentrations and reduce the risk of potential toxicity, but it is not necessary for co-administration with macitentan.

Prevalence and Prognosis of Hypothyroidism in Patients With Chronic Thromboembolic Pulmonary Hypertension: An Updated Review With Description of Case Series

Hypothyroidism has been shown to have several effects on organs, including derangements in the coagulation system, impairing endothelial function, but data on the importance of hypothyroidism in the pathogenesis and development of chronic thromboembolic pulmonary hypertension (CTEPH) are limited. This report presents an updated review of the prevalence and prognosis of hypothyroidism in patients diagnosed with CTEPH, including a detailed retrospective description of the series. The descriptive case series included 34 adult patients diagnosed with CTEPH, of whom 11 patients were diagnosed with hypothyroidism. The prevalence of hypothyroidism in CTEPH was found to be 32.35%. All patients with hypothyroidism had NYHA functional Class II-III. Hemodynamic values obtained through right heart catheterization (RHC) showed that patients with hypothyroidism had significantly higher mean pulmonary arterial pressures (mPAP), with a mean of 56.91 mm Hg vs 43.93 mm Hg (p = 0.026), and the PVR in dynes/sec/cm5 was 932 vs 541 (p = 0.027). Significant differences in PVR were found in wood units (WU) 11.91 vs 7.11 (p = 0.042). The mean level of brain natriuretic peptide (BNP) between both groups was 797.3 pg/mL for patients with hypothyroidism vs 262.02 pg/mL in patients with euthyroidism (p = .032). Hypothyroidism may significantly affect patients' clinical and hemodynamic outcomes in patients with CTEPH. Hypothyroidism as a risk factor in the evaluation and treatment of these patients is vital to optimize outcomes in CTEPH; further research is warranted whether hypothyroidism therapies could alter such outcomes.

The Relationship between Pulmonary Artery Pressure and Mortality in Type 2 Diabetes: A Fremantle Diabetes Study Phase II and National Echocardiographic Database of Australia Data Linkage Study

An elevated estimated right ventricular systolic pressure (eRVSP) identified on echocardiography is present in one-third of individuals with type 2 diabetes, but its prognostic significance is unknown. To assess the relationship between eRVSP and mortality, prospective data from 1732 participants in the Fremantle Diabetes Study Phase II were linked with the National Echocardiographic Database of Australia. Of this cohort, 416 (mean age 70.6 years, 47.4% males) had an eRVSP measured and 381 (91.4%) had previously confirmed type 2 diabetes. Receiver- operating characteristic analysis of the relationship between eRVSP and all-cause mortality was conducted. Survival analyses were performed for participants with type 2 diabetes diagnosed before first measured eRVSP (n = 349). Cox regression identified clinical and echocardiographic associates of all-cause mortality. There were 141 deaths (40.4%) during 2348 person-years (mean ± SD 6.7 ± 4.0 years) of follow-up. In unadjusted Kaplan-Meier analysis, mortality rose with higher eRVSP (log-rank test, p < 0.001). In unadjusted pairwise comparisons, eRVSP >30 to 35, >35 to 40, and >40 mmHg had significantly increased mortality compared with eRVSP ≤ 30 mmHg (p = 0.025, p = 0.001, p < 0.001, respectively). There were 50 deaths in 173 individuals (29.1%) with eRVSP ≤ 30 mmHg, and 91 in 177 (51.4%) with eRVSP > 30 mmHg (log-rank test, p < 0.001). In adjusted models including age, Aboriginal descent, Charlson Comorbidity Index ≥ 3 and left heart disease, eRVSP > 30 mmHg predicted a two-fold higher all-cause mortality versus ≤ 30 mmHg. An eRVSP > 30 mmHg predicts increased all-cause mortality in type 2 diabetes. Where available, eRVSP could inform type 2 diabetes outcome models.

Pulmonary Hypertension: Current Diagnosis, Approach and Treatment at the Dawn of the New European Guidelines

A turning point in the field of pulmonary hypertension (PH) is the most recent publication of the new European Guidelines for the diagnosis and treatment of pulmonary hypertension, a collaboration between the European Society of Cardiology and the European Respiratory Society [...].